1. Field of the Invention
Apparatuses consistent with the present invention relate to an image display apparatus, and more particularly, to a two-dimensional (2D) and three-dimensional (3D) image display apparatus having high resolution and low fabrication costs.
2. Description of the Related Art
A 3D image is provided in accordance with the principles of stereo vision. Binocular parallax, a characteristic due to the positions of the left eye and right eye located about 65 mm apart from each other, is the most important factor producing a 3D effect. 3D image displays can be divided into displays using glasses and glassless displays. Glassless displays are divided into parallax barrier-type displays and lenticular-type displays.
The parallax barrier-type and the lenticular-type are similar to each other in that a special optical plate, for example, a barrier or a lenticular lens, is located in front of/behind a display panel to spatially divide images seen from different viewpoints. The images from different viewpoints are separated and form certain viewing zones, and thus, a user can see a 3D image only when eyes of the user are located in the corresponding viewing zones.
The parallax barrier-type display alternately provides images that should be seen respectively by the left and right eyes in the form of a vertical pattern or a photo using an extremely thin vertical lattice column, i.e., a barrier. By doing so, a vertical pattern image that is to be provided to the left eye and a vertical pattern image that is to be provided to the right eye are separated by the barrier and images from different viewpoints are seen by the left and the right eyes, respectively, so that a stereo image is perceived.
According to a parallax barrier-type display disclosed in U.S. Pat. No. 5,315,377 and shown in FIG. 1, a parallax barrier 10 having openings 5 of a vertical lattice shape and masks 7 is disposed on a liquid crystal panel 3 having image information for the left eye (LE) Ln and image information for the right eye (RE) Rn of a viewer, and the image is separated through the openings 5 of the parallax barrier 10. The image information Ln input into the LE and the image information Rn input into the RE are alternately arranged in a horizontal direction on the liquid crystal panel 3.
For example, a pixel having the left image information Ln and a pixel having the right image information Rn become a set, and pixels on left and right sides of the opening 5 become pixels for different view points to form a 3D image. For example, a first image for the LE is perceived by the LE and a first image for the RE is perceived by the RE of the viewer, a second image for the LE is perceived by the LE and a second image for the RE is perceived by the RE of the viewer, and thus, left and right pixels are respectively perceived by the LE and RE.
According to the above display, the image is formed through the opening 5 and blocked by the mask 7, and thus, the images L are formed, e.g., at odd-numbered lines, and the images R are formed, e.g., at even-numbered lines, as shown in FIG. 2.
Therefore, the resolution of an image display is degraded, and the brightness of the 3D image is also degraded.
The barrier used for separating viewports is generally fabricated by printing periodically repeated stripes on a transparent film or a glass plate. However, the barrier can also be fabricated in an electrical way. Then, as shown in FIG. 3, a liquid crystal display (LCD) panel 28 performing as the barrier is further disposed on a front surface of a display panel 46 for displaying images. The LCD 28 can actively control the shape of barrier, however, since an additional LCD panel should be disposed besides the display panel for displaying images, fabrication processes become complex and fabrication costs rise.